<!DOCTYPE html>
<html style="font-size: 100px">
<head lang="en">
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width">
    <script src="jquery-2.0.3.js"></script>
    <link rel="stylesheet" href="立即下载.css">
    <title>立即下载</title>
</head>
<body>
  <div id="port">
   <div class="b1">
       <img style="height: 10rem;" src="image/76.png">
   </div>
      <div class="b2">
          <a href="#">
              <span>立即下载</span>
          </a>
      </div>
  </div>
</body>
</html>
<script>
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        function fullwidth(){
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                return ;
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